Descartes' enormously influential Meditations seeks to prove a number of theses: that God is a necessary existent; that our minds are equipped to track truth and avoid error; that the external world exists and provides us with information to preserve our embodiment; and that minds are immaterial substances. The work is a treasure-trove of views and arguments, but there are controversies about the details of the arguments and about how we are supposed to unpack the views themselves. This Companion offers a rich collection of new perspectives on the Meditations, showing how the work is structured literally as a meditation and how it fits into Descartes' larger philosophical system. Topics include Descartes' views on philosophical method, knowledge, skepticism, God, the nature of mind, free will, and the differences between reflective and embodied life. The volume will be valuable to those studying Descartes and early modern philosophy more generally.